HETA 98–0085–2715 Aurora Casket Company Aurora, … · Aurora Casket Company Aurora, Indiana Daniel J. Habes, M.S.E., C.P.E. ... The finished caskets are made of metal, having

HETA 98–0085–2715Aurora Casket Company

Aurora, Indiana

Daniel J. Habes, M.S.E., C.P.E.Dorothy Wigmore, M.S.

This Health Hazard Evaluation (HHE) report and any recommendations made herein are for the specific facility evaluated and may not be universally applicable. Any recommendations made are not to be considered as final statements of NIOSH policy or of any agency or individual involved. Additional HHE reports are available at http://www.cdc.gov/niosh/hhe/reports



This Health Hazard Evaluation (HHE) report and any recommendations made herein are for the specific facility evaluated and may not be universally applicable. Any recommendations made are not to be considered as final statements of NIOSH policy or of any agency or individual involved.


applicable. Any recommendations made are not to be considered as final statements of NIOSH policy or of any agency or individual involved. Additional HHE reports are available at http://www.cdc.gov/niosh/hhe/reports

http://www.cdc.gov/niosh/hhe/reports



ii

PREFACEThe Hazard Evaluations and Technical Assistance Branch of NIOSH conducts field investigations of possiblehealth hazards in the workplace. These investigations are conducted under the authority of Section 20(a)(6)of the Occupational Safety and Health Act of 1970, 29 U.S.C. 669(a)(6) which authorizes the Secretary ofHealth and Human Services, following a written request from any employer or authorized representative ofemployees, to determine whether any substance normally found in the place of employment has potentiallytoxic effects in such concentrations as used or found.

The Hazard Evaluations and Technical Assistance Branch also provides, upon request, technical andconsultative assistance to Federal, State, and local agencies; labor; industry; and other groups or individualsto control occupational health hazards and to prevent related trauma and disease. Mention of company namesor products does not constitute endorsement by the National Institute for Occupational Safety and Health.

ACKNOWLEDGMENTS AND AVAILABILITY OF REPORTThis report was prepared by Daniel J. Habes and Dorothy Wigmore of the Hazard Evaluations and TechnicalAssistance Branch, Division of Surveillance, Hazard Evaluations and Field Studies (DSHEFS). FieldAssistance by Rick Driscoll. Desktop publishing by Ellen Blythe. Review and preparation for printing wasperformed by Penny Arthur.

Copies of this report have been sent to employee and management representatives at the Aurora CasketCompany and the OSHA Regional Office. This report is not copyrighted and may be freely reproduced.Single copies of this report will be available for a period of three years from the date of this report. Toexpedite your request, include a self–addressed mailing label along with your written request to:

NIOSH Publications Office4676 Columbia ParkwayCincinnati, Ohio 45226

800–356–4674

After this time, copies may be purchased from the National Technical Information Service (NTIS) at 5825Port Royal Road, Springfield, Virginia 22161. Information regarding the NTIS stock number may beobtained from the NIOSH Publications Office at the Cincinnati address.

For the purpose of informing affected employees, copies of this report shallbe posted by the employer in a prominent place accessible to the employeesfor a period of 30 calendar days.

iii

Health Hazard Evaluation Report 98–0085–2715Aurora Casket Co.

Aurora, IndianaOctober 1998

Daniel J. Habes, M.S.E., C.P.E.Dorothy Wigmore, M.S.

SUMMARYOn January 14, 1998, the National Institute for Occupational Safety and Health (NIOSH) received a request fromthe International Brotherhood of Boilermakers, on behalf of local M–300 of the Aurora Casket Co. in Aurora,Indiana. The union asked NIOSH to evaluate concerns that repetitive motion injuries and other musculoskeletaldisorders may increase with the introduction of a new production method in the sewing and interior parts casketmanufacturing departments.

NIOSH representatives conducted an evaluation April 20–23, 1998. This included videotaping of the job tasks inthe sewing/interior departments, review of the Occupational Safety and Health Administration (OSHA) Log andSummary of Occupational Injuries and Illnesses (OSHA Form 200), and distribution of a medical andmusculoskeletal disorders symptom questionnaire to the workers.

The OSHA logs indicated that from 1995 to 1998, about 10% of the Company’s injuries and illnesses occurred inthe “interior” departments (41/346), 83% of which (34/41) involved strains and sprains of the neck, back,shoulders, arms, hands, and wrists. All 49 workers who completed the questionnaires indicated some type of achesand pains, mostly to the shoulders, back, legs, and feet. Many workers also reported that working in the newworkstation modules (cells) was associated with high levels of psychological stress.

The ergonomics evaluation showed that the main musculoskeletal stressors were prolonged standing whileperforming work tasks, excessive reaching to cut material, unassisted lifting of heavy rolls of materials, andhandling/transporting finished casket interior components.

NIOSH investigators conclude that there is a high risk of musculoskeletal injury to workers at theAurora Casket Company who stand for prolonged periods without accommodation for sitting, liftheavy rolls of material from shelves to the workstations, handle bundles of finished materials, andreach across wide tables while cutting materials. Recommendations addressing these and otherissues related to the work tasks are contained in this report.

KEYWORDS: SIC 3994 (Casket linings), sewing, stapling, TSS, work modules, lifting, repetitive motion,prolonged standing, musculoskeletal disorders, back pain, postural fatigue, psychological stress.

TABLE OF CONTENTSPreface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii

Acknowledgments and Availability of Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Job Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Cutting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Aurora Plant (Hill) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Vanguard Plant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Interior Sewing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Panel Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Ergonomic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Medical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Evaluation Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Medical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

OSHA 200 Logs Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Vanguard Plant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Aurora (Hill) Plant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Questionnaire and Body Maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Body Maps – General Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Body Maps – Specific Comparisons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Ergonomic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Cutting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Sewing Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Panel Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Sewing: Standing versus Sitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Miscellaneous Observations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Medical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Ergonomic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Cutting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Appendix A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Appendix B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Page 2 Health Hazard Evaluation Report No. 98–0085

INTRODUCTIONOn January 14, 1998, the National Institute forOccupational Safety and Health (NIOSH) received arequest from the International Brotherhood ofBoilermakers, on behalf of local M–300 of theAurora Casket Co. in Aurora, Indiana. The unionasked NIOSH to evaluate concerns that repetitivemotion injuries and other musculoskeletal disordersmay increase with the introduction of a newproduction method in the sewing and interior partsmanufacturing departments.

NIOSH representatives visited the site April 20–23,1998. This visit included an opening conference,attended by management and union representatives;a walk–through inspection of the entire facility;videotaping of the job tasks in the sewing/interiordepartments; review of Occupational Safety andHealth Administration (OSHA) Log and Summaryof Occupational Injuries and Illnesses (OSHA Form200); and distribution of a medical andmusculoskeletal disorders symptom questionnaire tothe workers. The closing conference was held on theafternoon of April 23, 1998.

BACKGROUNDAurora Casket Co. has been producing coffins inAurora, Indiana, since 1890. The company employsabout 380 workers in two plants (Vanguard andAurora [the “Hill”]), one–half of whom have tenureof 10 years or more. For most of the time AuroraCasket has been in business, workers made theinteriors seated at standard workstations, most ofwhich were for sewing. After seeing ademonstration at an industry trade show, companyofficials decided to introduce a modular (or cell)method known as the Toyoda Sewing System (TSS).Its main element is to have workers stand and rotatethrough the various tasks in a cell of workstationsuntil a completed piece is produced. This replacesthe traditional “bundle” production method in whichworkers at a given workstation continually producethe same piece components, passing them in bulk to

the next station. TSS is supposed to provide greateroutput with fewer workers than the bundle style ofproduction by reducing material handling andstorage costs.

The change to the TSS system required the purchaseof new sewing machines and adjustableworkstations, and training for workers. Theseactivities were completed at the Vanguard plant inNovember 1997 but were not fully in place at theAurora (“Hill”) plant at the time of the NIOSH visit.The TSS system also included changing from hourlywages to a group incentive pay plan at Vanguard,and from an individual to group incentive plan at theAurora plant. Vanguard occupies the Company’s original 1890site, producing standard-gauge steel caskets withlittle variety in interior and exterior styles. The“Hill” is the newer of the two plants, producingstandard- and heavy -gauge caskets, made ofmaterials such as stainless steel, bronze, and copper,with a large variety of interior materials and exteriorfinishes. Work schedules are standard 8–hour shiftswith ½ hour for lunch and 15–minute breaks in themorning and afternoon. There are two shifts at theAurora plant, while the Vanguard plant worked onlythe 7:00 a.m. to 3:30 p.m. shift. Because of the dropin output that occurred while the TSS system wasimplemented, workers in the new cell modules atboth plants worked mandatory overtime to completea full day’s production. The main work tasksevaluated in the interior departments at the Hill andVanguard plants were cutting, sewing, and panelassembly. All workers observed during theevaluation of these tasks were women.

Job DescriptionsThe finished caskets are made of metal, having eithera full (“hinge”) or ½ lid. The inside of the casketincludes the pillow and the throw, and the materialthat is visible while viewing an open casket is calledthe throwout. Other interior components of a casketare the lining and the overlay (the part that covers theclosed part of the casket). These components areproduced by the sewers. The lids are finished withupholstered cardboard materials, which are made in

Health Hazard Evaluation Report No. 98–0085 Page 3

the panel departments. Specific job descriptionsfollow.

Cutting

Aurora Plant (Hill)

Cutters use bulk rolls of material to make patterns foruse in the sewing and panel cells. Most of thematerial is cut in bulk from 48–inch wide rolls on along cutting table. The cutter loads the roll ofspecified material onto a mechanical spreader whichdistributes layers of material on the table so thatmany patterns can be cut at one time. The cuttingtable is 35.5 inches (in.) high and 73 inches wide.The spreader rides on tracks located on the edge ofthe table. After the material is spread, the cutter laysa pattern on the material, marks the cut lines with achalk pad, and cuts the layers of material with eithera hand–held electric cutter or a large stand–up cutter,depending on the number of layers being cutsimultaneously.

Material cut in low volume, or patterns made with60-inch-wide material, are cut by hand at separatenearby tables. The cuts are made on single sheets ofmaterial with conventional shears. These tables areabout 36 inches high, and surrounded by mats. Thethree workers at the separate tables, and the twoworkers operating the spreader and the pattern cutter,rotate positions during the work day. In eachposition, the rolls of material are lifted and carried tothe cutting tables by the worker from nearby shelves,ranging in height from 14 to 77 inches. The rollsrange in weight from 25 to 90 pounds. Thefrequency of lifting varies during the day dependingon product mix, but is usually two or three lifts perhour. Rolls of material can be entirely used oncethey are on the cutting table, or they can be carried toand from the cutting tables several times during theday. After they cut and fold the material, the cutterscarry the bundled pieces to the interior and panelmodules by hand, or place them on a rolling cart forthe supplier to move.

Two other jobs were observed in the cutting area:cutting wadding, and surging. Wadding is cushioned

material used as the backing of a pattern orsandwiched between two layers of material. It is cutat a standard cutting table (48-in. wide) with atrack–mounted electric shear, equipped with a30–inch long handle. The worker unravels theappropriate amount of material onto the track, andmakes the cut by sliding the shear along the track.The wadding width varies from 16 to 36 inches. Atthe time of the NIOSH visit, material 20 inches widewas being cut.

Surging is a stand-up task where material is fedthrough a machine which applies a straight andfinished edge. The worker reaches for raw materialsfrom the top shelf of a multi–tiered cart (51 inches)and places finished materials on the middle tier ofthe cart (36 inches). The height of the surge tablewas about 40 inches. In an area adjacent to thecutting area, surging was also done as a seated task.

At the time of the NIOSH evaluation, the cuttingarea was functioning in the bundle productionmethod described earlier. Company plans were toeventually integrate these job tasks into a module,along with the interior sewing and panel modules.

Vanguard Plant

At the older Vanguard plant, one worker wasresponsible for the cutting table. She operated thespreader, cut the patterns, and delivered materials tothe sewing and panel modules. The operation of thespreader and cutting of the patterns was similar tothat at the Aurora plant. The cutter also loaded andoperated the shearer, a machine that bonds twolayers of material together using heat and embossesa raised pattern onto the two layers to produce astitched pleat effect. (This job was not observed atthe Aurora plant.) The cutting of 60-inch materialwas not observed at Vanguard. Even though themodular concept was more fully implemented atVanguard than at Aurora, there were plans torearrange and relocate the modules, possiblyaffecting the cutting operations at this location.

Interior Sewing


Except for noted differences, the sewing modules atVanguard and the Hill were the same. Each had twosewing modules. Each was set up in the shape ofthree sides of a rectangle with either three or fourworkers and six sewing machines. The floor spaceranged from 20 to 30 feet long and 6 to 8 feet wide.Each sewing machine was installed on anadjustable–height workstation and operated by footpedals that could be adjusted for position and right orleft foot activation. All workstations in both plantswere adjusted to 39–44 inches in height. For eachworkstation, the distance from the edge of the tableto the needle on the sewing machine was about 10inches. Effective reach distances to the sewingneedles were about 17 inches because the workershad to stand away from the table edge to allow forclearance of material and to operate the foot pedals.Material for the interior components was in themodules, some laying on standard height carts (36inches) and some hanging above the surface of theworkstations at 75 inches. At any given time, amodule is supposed to be producing two completeassemblies. The TSS method of sewing provides fortime balance among sewing operations by a methodcalled back–bumping. The last operation in theprocess is designed to take the least amount of time.When the sewer in that position completes anassembly, the worker goes to the first position,“bumps” the work there, and each worker moves tothe next position in the cell. The theory is that nosewer has to wait or hurry up to keep pace with anyother worker in the module.

The Aurora plant had a seated sewing area thatproduced assembly types that had not yet beenintegrated into the cells. Examples include interiorcomponents made of velvet and components forhinge-lid caskets. Hinge lids are on caskets that openfully, as opposed to the more common ½ –lid styles.Hinge-lid components were being produced atVanguard at the time of the visit. They are sewn inthe same manner as the ½ lids but require thealignment and movement of materials up to 132inches long. These units usually comprise less than10% of a day’s production.

Panel Assembly

Two panel modules at the Aurora plant and one atVanguard produced the interior components for thecasket lids. The panel modules were shaped like thesewing modules, ranging in length from 24 to 30 feetand in width from 5 to 7 feet. The center and sidepanels of the casket lid are stapled or glued tocardboard panels during the various operations. Theworkers stand at the same type of workstations foundin the sewing modules. The staple guns areair–powered, operated with a finger trigger. Some ofthe staple guns were counter–balanced withoverhead mounting systems, while others weresituated on the table top. At Vanguard, there weretwo table–top staple machines that resembled sewingmachines, (called mini–stitchers); they wereoperated by a single foot pedal. Most of thematerials were within the easy reach of the workerabove the level of the table, while some of thecardboard panels were situated below table height.Finished panels are stacked on either flat ormulti–tiered carts and later transported to theassembly departments by members of the panelmodules. At Vanguard, the table heights were set atbetween 36 and 39 inches. At Aurora, the tableheights in the panel cells were adjusted between 37and 40 inches.

METHODS

ErgonomicThe ergonomic evaluation included a walk–throughsurvey of the “interior” manufacturing areas of theVanguard and Aurora plants to determine how thejobs are performed and some discussion withemployees. Representative jobs in the cutting, panel,and sewing areas of each plant were videotaped todocument the postural demands and repetitiveness ofthe jobs. This information was extracted from thevideo through playback analysis in real time or inslow motion.

Medical


The medical portion of the evaluation included areview of the OSHA 200 logs from 1995 to April1998, interviews with workers, and distribution of ashort medical questionnaire to all workers who werein the areas investigated during the NIOSH visit. Inthe questionnaire, those who had pain or discomfortin the last 12 months were asked to fill in a “bodymap” indicating the location of pain, the extent towhich it hurt (0 “no pain” to 5 “worst imaginablepain” scale), and what they thought caused the pain.A copy of the questionnaire and body maps can befound in Appendix B. Workers were not restricted torating their aches and pains on general areas of themaps, e.g., the upper arm or the neck/shoulderregion. They could indicate their aches and painswherever they were felt. Each entry made on thebody maps was recorded as an “instance.” Theinstructions given to the workers allowed them toindicate more than one instance of aches or pain orintensity on a general area of the body. The workerswere also asked to report any other information theyconsidered to be important.

EVALUATION CRITERIAOverexertion injuries, such as low back pain,tendinitis, and carpal tunnel syndrome, are oftenassociated with job tasks that include: (1) repetitive,stereotyped movement about the joints; (2) forcefulmanual exertions; (3) lifting; (4) awkward and/orstatic work postures; (5) direct pressure on nervesand soft tissues; (6) work in cold environments; or(7) exposure to whole–body or segmental vibration(Armstrong, Radwin, and Hansen 1986; Gerr, Letzand Landrigan 1991; Rempel, Harrison and Barnhart1992). The risk of injury appears to increase as theintensity and duration of exposures to these factorsincreases and recovery time is reduced (Moore andGarg 1995). Although personal factors (e.g., age,gender, weight, fitness) may affect an individual’ssusceptibility to overexertion injuries/disorders,studies conducted in high–risk industries show thatthe risk associated with personal factors is smallcompared to that associated with occupationalexposures (Armstrong, et al. 1993).

In all cases, the preferred method forp reven t i ng/ c o n t r o l l i n g w o r k– r e l a t e dmusculoskeletal disorders (MSDs) is to design jobs,workstations, tools, and other equipment to matchthe physiological, anatomical, and psychologicalcharacteristics and capabilities of the worker. Underthese conditions, exposures to task factors consideredpotentially hazardous will be reduced or eliminated.

The criteria used to evaluate the jobs at theVanguard and Aurora plants were workplace and jobdesign criteria found in the ergonomics literature andrecommendations for acceptable lifting weights asdetermined by the NIOSH Revised Lifting Equation(Waters, et al. 1994).

The NIOSH lifting equation (NLE) is a tool forassessing the physical demands of two–handedlifting tasks. A full description of the components ofthe NLE is provided in Appendix A. In brief, theequation provides a recommended weight limit(RWL) and a lifting index (LI) for a lifting task,given certain lifting conditions. The RWL is theweight that can be handled safely by almost allhealthy workers in similar circumstances. The LI isthe ratio of the actual load lifted to the RWL. Liftingtasks with an LI <1.0 pose little risk of low backinjury for the majority of workers. Tasks with an LI> 1.0 may place an increasing number of individualsat risk of low back injury. Many researchers believethat tasks with an LI > 3.0 pose a risk of back injuryfor most workers (Waters, et al. 1994).

RESULTS

Medical


OSHA 200 Logs Review

Vanguard Plant

Interior and panel workers at Vanguard accountedfor one of 25 reported injuries or illnesses for thewhole plant in 1995, 2 of 34 in 1996, 9 of 38 in 1997,and 2 of 14 for the first four months of 1998. Ofthese 14 total entries for the period reviewed, 12were for “strains” of the back, shoulders, wrist and/orneck. Recorded as injuries, rather than illnesses, thestrains led to three workers being off the job and laterhaving restricted duty, three others on restricted duty,and no lost time or restrictions for the remainingworkers.

Aurora (Hill) Plant

Panel and interior workers at the Aurora plantaccounted for 6 of 72 injuries and illnesses in 1995(5/6 musculoskeletal–related), 5 of 68 in 1996 (4/5musculoskeletal–related), 14 of 67 in 1997 (12/14musculoskeletal–related), and 2 of 28 for the firstfour months of 1998 (½ musculoskeletal–related).The 22 entries affecting the musculoskeletal system,reported as strains/pains/disorders to the back,shoulder, wrist and/or neck, were logged as injuries,15 of which required no lost time or restricted work.

Questionnaire and Body Maps

Forty–nine of the distributed questionnaires werereturned to the NIOSH investigators from workers atboth plants (38 from Aurora and 11 from Vanguard);all respondents were women. At Aurora, cuttersaveraged 46 years of age and 14 years tenure; panelworkers and sewers averaged 48 years of age and 16years of service. At Vanguard, cutters averaged 41.5years with 8 years experience, sewers averaged 44years with 11 years seniority, and the average age ofpanel workers was 46 with 16.5 years on the job.

All 49 workers reported some kind of ache or pain inthe previous 12 months, almost all of which theyassociated with their work. A complete picture ofthe workers’ reports of musculoskeletal aches andpains can be found in the body maps in Appendix. B.

There is one body map for each of the main areas atthe Vanguard and Aurora facilities. The cell materialhandlers were included with the cell sewers at eachplant. The scale for pain intensity was compressedfor reporting purposes such that a score of 1 wasdesignated as “low,” scores of 2 and 3 were labeled“medium,” and scores of 4 and 5 were called “high.”If workers indicated a range in their scale recording,the average was calculated.

Body Maps – General Results

Aurora workers reported more aches and pain thanthe Vanguard workers. The cutters at Aurorareported the most pain overall, with 25 indications atthe neck, shoulder, and back, the number of aches atthe lower leg and feet among the Aurora cutters wascomparable to other groups. Twelve of the cutters’25 indications at the neck, shoulder, and back wereof the highest intensity. Vanguard panel workersreported the least amount of pain overall, includingjust one instance of medium foot pain. However,they were also the smallest group. Aurora plant(Hill) panel workers reported as much neck,shoulder, and back pain as the Hill cutters (26instances, 13 high intensity) but not as much footpain as the cutters. Sitting sewers at the Aurora plantreported more neck, shoulder, and arm/wrist painthan their standing counterparts, but no foot or lowerleg pain.

Body Maps – Specific Comparisons

At Vanguard, seven workers in the two sewingmodules reported medium- and high-intensity achesand pains in the neck, shoulders, lower back, elbow,wrists, knees, and feet. No knee or foot problemswere recorded within the last year on the OSHAlogs, and only one musculoskeletal probleminvolving the knee was reported during the1995–1998 time period. Similarly, four workers atVanguard reported symptoms in the area between ornear the shoulder blades, but only one entry forshoulder problems was found on the OSHA 200 logsin the last year.


Workers linked their aches and pains in the upperextremities (hands, arms, neck, and shoulders) torepetitive motion, unfolding material, the way theystand, and the foot pedal position. They associatedaches and pains in the legs and feet with overtimework and standing too long.

Aurora plant and Vanguard panel workers reportedaches and pains in their lower back, neck, shoulder,wrist, and legs/feet. Aurora panel workers, inparticular, noted high-intensity aches and pains in theupper back, elbow, and neck. Panel workers at bothplants attributed neck and shoulder pains to workingwith their head bent all day, psychological stress,reaching, repetition, pulling panels through thegluing machine (Aurora), and general overuse of theright arm. They linked arm and hand/wrist aches andpains to staple gun use, lifting materials at the worktable, and repetition. They associated back problemswith stress, standing, looking down at the work,lifting and pushing carts, and adjusting tables. Theyattributed leg and foot pain to pushing carts andstanding all day.

At Aurora, there was a noticeable difference in thedistribution of aches and pains between the workerswho still sat at their work and those who were in themodules. Five workers who were still sittingcompleted body maps. They reported 18 instances ofpain in the neck and shoulder area (7/18 highintensity), 5 for the lower back, and none involvingthe feet. The 14 workers in Aurora sewing cellsreported 13 instances of pain in the neck andshoulders, 2 in the low back, and 21 instances ofaches and pains in the lower legs and feet. Standing,especially with their weight on one foot, dominatedthe reasons workers in the sewing modules at Auroragave for their leg and foot pain. Tension, reachingtoo high for parts, lifting material rolls, adjustingwork surface heights and pulling and turningmaterial were cited as the cause of neck and shoulderproblems.

Many workers thought chairs would reduce theiraches and pains, whatever the workstationarrangement. Both the sitting and the standingsewers at Aurora indicated that stress levels were

increasing from quotas and the pressure to produce.Many were concerned about heat in the summer andthe lack of proper ventilation to cool their workareas.

Workers in the cutting jobs at the Aurora plantreported aches and pains in both upper and lowerextremities and headaches linked to stress. Theirmusculoskeletal symptoms were similar to those ofthe other workers, involving the feet, knees, hips,lower back, neck and shoulder, elbows, andhand/wrist. However, they reported more aches andpains than other workers.

Cutters linked their pain to stress, repetitive motion,moving material trucks, lifting, and improper worksurface heights. Neck and shoulder aches and painswere linked to reaching, and hand and wristproblems were attributed to gripping scissors andusing power saws and knives. Back problems amongcutters were attributed to non–adjustable work tables,and foot problems to standing and inadequate floormats.

The workers also consistently referred to three issuesin their general comments: stress, heat, andventilation. Other issues included lack of emergencyexits and poor lighting, uncleanliness of thewashrooms, lack of chairs for breaks, and inadequatespace in the eating area at the Hill plant for breaksand lunch. A complete list of worker concerns canbe found in Appendix B.

Workers in all areas of both plants reported thatstress levels had increased in the last year. In boththe written comments and interviews, stress wasoften linked to the new sewing cells and relatedproduction quotas. Some workers linked stress tomusculoskeletal problems in the neck, shoulder,and/or back.

Ergonomic


Cutting

The main ergonomic stress factors in the cuttingareas for both plants were the long reaches requiredto mark and cut patterns on the spreading tables (upto 48 in. at Vanguard and 60 in. at Aurora), having tolift rolls of material for transport to and from thestorage shelves, and the material handling required todeliver finished materials to the sewing and panelmodules. The 48– and 60–inch reaches at the Auroraplant were made once per set, or about once every 15minutes per worker. In making these cuts, workersleaned over the table and stood on one foot tocomplete the task. Most of the other cutting at themanual tables involved shorter reach distances, donewith the electric shears as the material was beingfolded and then cut. This folding required someadditional material handling and awkward posturesof the cutters’ wrists and shoulders.

Other observed postural stresses in the cutting areawere bending over to reach the scanner keypad onthe spreader (height =19 inches), and shoulder andforearm extension from using the cutting machine inthe wadding area. These postures were associatedwith the wadding cut task because of the length ofthe handle on the cutter (30 inches) and because thecutting tool was moved the entire length of thecutting track (48 inches) when the material being cutwas less than ½ that amount.

Using the NLE to assess the lifting of rolls ofmaterial from the storage racks to the attachmentspindles on the spreader or the cutting tablesindicates that the rolls should weigh no more than26-30 pounds to provide a lifting index = 1. Theassumptions underlying this weight range are thatlifts are compact and made occasionally, initiallifting heights are from 14 to 77 inches (thedimensions of the storage racks) and the rolls ofmaterial could be lifted safely by the majority of theworker population. Lifting rolls of material thatweigh 90 lbs would result in a lifting index of greaterthan 3, which is a hazardous lifting condition formost workers. For more details about the NLE, seeAppendix A.

Sewing Modules

The primary ergonomic risk factor observed in thesewing modules was the requirement to stand, oftenon one foot, without being able to sit. Much of thestanding was in a prolonged static posture because,in general, the sewers in the modules were notrotating through positions in the TSS prescribedback–bumping manner. When they did rotate, it wasusually after each worker had completed the task shebegan at her workstation. Sewers stood on one footat times because foot pressure has to be releasedfrom the pedal as pieces of material were realignedand repositioned on the work surface. Intermittentapplication of pressure on the foot pedals wasobserved to be more frequent during sewing of largepieces of material together, such as in blankets orthrows used in hinged-lid components.

In general, standing work should be designed so thatreach distances do not exceed 20 inches, andworkplace heights should be below elbow height,which for the average woman is 40.5 inches ( +about 2 inches). When sustained activity is notrequired and the bend is made at the hip or waist,reaches can be as much as 32 inches (EastmanKodak 1983). For work requiring downward forces,such as moving material forward while sewing, thework height should be about two inches below elbowheight (Konz 1979). The height and reach distancesobserved in the sewing modules at both Aurora andVanguard (about 17 in. maximum reach and 39–44in. workstation height) were consistent with theseworkstation design guidelines, considering individualdifferences. In some cases, the workstations thatsewers rotated to were adjusted to heights abovetheir own standing elbow height.

The primary concern regarding the design of theworkstations at the two plants was whether workersshould be sitting or standing.

In general, seated workstations are preferred when:

1. Items needed for the task cycles can be easilysupplied and handled within the work space2. Foot pedals are used


3. Hand forces greater than 10 lb are not required4. Fine assembly or precision tasks are done for themajority of the shift

Standing workstations are preferred when:

1. The workstation does not have knee clearancefor a seated operation

2. Objects weighing more than 10 lb are handled3. High, low, or extended reaches in front of thebody are frequently required4. Operations are physically separated and requirefrequent movement between operations5. Downward forces must be exerted, as inwrapping and packing operations

Table 1Preferred Workstation Selections Based on Task Parameters (Eastman Kodak, Vol. I)

Parameters HeavyLoadand/orForces

Inter–mittentWork

ExtendedWorkEnvelope

VariableTasks

VariableSurfaceHeight

RepetitiveMovements

VisualAttention

FineManipulation

Duration >4 Hours

Heavy Load and/orForces

ST ST ST ST S/ST S/ST S/ST ST/C

Intermittent Work ST ST ST S, S/ST S, S/ST S, S/ST S, S/ST

Extended WorkEnvelope

ST ST S/ST S/ST S/ST ST/C

Variable Tasks ST S/ST S/ST S/ST ST/C

Variable SurfaceHeight

S S S S

RepetitiveMovements

S S S

Visual Attention S S

Fine Manipulation S

Duration > 4 HoursNote: S=sitting; ST=standing; S/ST = sit/stand , ST/C = standing, with chair available

Table 1 provides similar and additional guidanceabout determining the set up of workstations basedon task parameters. The table groups taskcharacteristics in pairs and provides the preferredworkstation type in the intersecting box. The taskcharacteristics of “duration > 4 hours,” “finemanipulation,” “visual attention,” “repetitivemovements,” and “variable surface height,” are allassociated with sewing. Combining them, thepreferred workstation type is always sitting. When“heavy load/forces,” “intermittent work,” and“extended work envelope” (long reach distances) arecombined (none of which are usually required insewing), the preferred workstation type is standing.

All other combinations of the task characteristicsresult in some combination of sitting and standing orstanding with chair available as the preferredworkstation design.

The criteria listed above (but not Table 1) state thatstanding should be considered if operations arephysically separated and require frequent movementbetween operations. This is a task parameter in thesewing modules when the jobs are performed as TSSprescribes.

Each module was adequately furnished with padded


surfaces for standing, and most workers appeared tobe wearing sensible, cushioned shoes. Floor space inthe modules was limited, confined further by thepresence of material carts and racks.

Panel Modules

The main ergonomic stressors in the panel moduleswere having to stand all day and holding andoperating the staple guns. Fastening materials to thecardboard backing also required pulling the materialtight as the stapling took place. This was less evidentat the Hill plant than at Vanguard because many ofthe materials were glued at the Hill plant. Someimpact force or “jerk” was transferred to the hand asthe staples were driven against the metal workstationsurface, but this force could not be measured.Typical lid assemblies required 85 staples, andhinged lids took as many as 115. Flipping the panelassemblies while attaching sides to the center panelrequired rotation and flexion of the shoulders. Thepanel modules were better suited to standing than thesewing modules because fewer foot pedals wereused. Also, operating the pistol–grip staple guns atseated workstations would require flexion of thewrist unless the table tops were tilted toward theworker. Standing enabled the workers to maintain amore neutral wrist posture while stapling with thepistol handled tools.

Sewing: Standing versus Sitting

Several video sequences were analyzed to determineif there was a difference in the time or effort requiredto sew standing versus sitting. There were sittingoperations only at the Hill plant, and these were foroperations not yet assigned to modules. As such, adirect comparison of the time required to sewstanding as opposed to sitting was not possible.However, a few video sequences were analyzed in anattempt to discern any differences between the twomethods.

First, measurements were made of the time needed toperform a sub–task called “needle passes,” (pushingaligned materials through the needle of the sewingmachine before deactivating the foot pedal and

pausing to realign materials). Depending on thecomponent being made, the material, and the numberof materials to be aligned per pass, the length of apass could be 4 to 12 inches. Sewing an entire sideof a pillow (about 30 inches) could be accomplishedin one pass and was observed in both methods. Onetime study comparison examined assemblingpillows: the first video sequence was of a silk pillowmade by a standing worker at Vanguard, and theother a velvet pillow made by a sitting worker atAurora. The sequence at Vanguard lasted 55seconds, and the average time per pass was 1.7seconds. The sequence at Aurora lasted 49 seconds,and the average time per pass was 1.9 seconds.

Second, other video sequences were analyzed tocalculate the amount of cycle time that sewingcomprises for purposes of determining how muchtime could potentially be saved if there actually wasa difference in sewing time between standing versussitting, even though this was not able to bedetermined with the video sequences collectedduring this evaluation. For a number of videosamples of standing workers lasting 16.3 minutes, theactual time sewing was 7.5 minutes or 46%. Videosamples lasting 15.7 minutes for sitting workersindicated that 9 minutes, or 57% of the time, wasspent sewing. Workers in each group spent theremainder of their time getting material, aligningedges, cutting with the scissors, measuring parts,folding completed assemblies, and testing theintegrity of seams and corners. Standing sewersseemed to have an easier time getting materials anddisposing of finished parts, while sitting workersappeared to more easily align and maneuver parts atthe workstation. At sitting workstations, workers arecloser to the sewing machine needle, whichdecreases reach and viewing distances.

Miscellaneous Observations

There were no chairs for workers to sit on in themodules during breaks or when the flow of work wasinterrupted, such as when materials were beingdelivered to the assembly areas. There were notenough seats in the cafeteria to accommodateeveryone who was on lunch break at the same time,


so some workers sat on the floor or on makeshiftseats in their work areas while eating.

The workstations at Vanguard and Aurora weresimilar in design and adjustability, but those atVanguard were less substantial and less stable. Atthe Aurora plant, metal troughs were mounted in thefront and back of the workstations to accommodatelong pieces of material. The Vanguard workstationsdid not have the troughs, making it difficult tomaneuver long pieces of material during sewingoperations. One worker sewing hinged lidcomponents placed the material in a waste materialbasket to avoid dragging it on the floor as anoperation was being performed.

The staple guns were quieter at Aurora than atVanguard, although the equipment and layout wasessentially the same at both locations.

DISCUSSION

MedicalThere were some differences in the way workersreported the location and intensity of aches and painson the body maps. Some workers reported multipleinstances of pain in what could be considered onegeneral body area. For example, five sitting sewersand nine panel workers at the Hill reported 21 and 15instances of pain in the shoulder/neck region,respectively. This may make it seem like their painin those areas was dramatically worse than theirstanding and Vanguard counterparts. However thebody maps are interpreted, what is most importantabout the information obtained from them is that allworkers reported pain to the shoulder/neck, back andupper extremity, and standing workers reported morelower leg and foot pain than sitting workers.

There are two possible explanations for thedifference between the OSHA 200 logs and theworkers’ body maps and comments. The employeeseither work in pain and don’t report their injuries, ormost of the aches and pains have occurred in therelatively short time since the modular cells were put

in place. Considering the work force’s age and yearsof experience, the former is likely the case.However, the introduction of the modules did alterthe exposure to musculoskeletal injury risk factorsfor all workers, even those at the Aurora plant whocontinued to sit and sew. These workers, who usedto sew the complete line of interior products made bythe company, began to work exclusively on thecomponents not yet done in the sewing modules.Typically, these were the most difficult items to sew– the heavy velvet buggy patterns and the largerhinged-lid interiors and blankets. For those sewersassigned to modules, much of the pain reported,particularly to the lower extremity, likely got worsesince the work cells were implemented. A recentstudy of workers at an appliance factory found thatworkers who stood for more than four hours per day,or who stood and used foot pedals, reportedsignificantly more lower extremity aches and painsthan workers not having these job exposure factors(MacDonald, et al. 1998). At the Hill and Vanguardplants, long work days likely increased the frequencyand severity of the aches and pains reported.

Vanguard workers may have reported fewer achesand pains because of the fewer and simpler stylesproduced there, or it may be an indication that theworkers were becoming accustomed to working inthe cells. Unaccustomed repetitive work has longbeen associated with the development of cumulativetrauma disorders to the upper extremity (Conn 1931;Wilson and Wilson 1957). The workers at the Hillplant, who had not been fully trained to work in themodules, and were not used to standing whileworking, may have experienced a similarunaccustomed work reaction to both the upper andlower extremities.

Many workers reported that social factors associatedwith working with others in the modules, thepressures to meet production quotas, and the low jobcontrol within the modules caused a great deal ofstress, which led to or exacerbated their physicalproblems. Many further reported that theenvironmental issues that bothered them, such asheat and ventilation, added to their stress. Acomprehensive review of psychosocial factors and


work–related musculoskeletal disorders concludedthat monotonous work, high perceived work load,time pressures, and lack of social support wereassociated with the onset of such disorders (Bongers,et al. 1993). Another study linked psychosocialfactors to musculoskeletal disorders in a populationof garment workers (Brisson, et al. 1989).

Finally, a recent follow–up study of the associationsbetween psychosocial factors at work and back andlimb disorders concluded that work organizationissues seemed to predispose workers tomusculoskeletal disorders (Leino 1995).Recognition of this association may be important inefforts to prevent further problems.

ErgonomicA primary theme regarding the NIOSH evaluation atAurora Casket Co. was evaluating whether or not thecell production method increased the workers’ risk ofinjury. Results notwithstanding, sewing tasks havehistorically been associated with musculoskeletaldisorders, particularly to the neck and shoulders(Vihma, et al. 1982) and the upper limbs (Punnett, etal. 1985). The videotape analyses showed littledifference in the involvement of the upper extremitybetween working sitting and standing, so no matterwhat is concluded regarding this theme, jobs at thecompany (if unchanged) will remain risk factors formusculoskeletal disorders. The reports ofmusculoskeletal aches and pains among the sewerswho have always sat is further confirmation of thegeneral risk of sewing machine work.

It is not surprising that the Aurora plant cuttersreported the most aches and pain. (The one cutter atVanguard was included with the sewers, a groupwhich also reported a substantial number of achesand pains.) The cutters’ jobs required more liftingand more reaching than any group in either plant.Most of the rolls of material they lifted and carriedweighed more than the maximum 26–30 pounds thatthe NLE indicated should not be exceeded. Thereach distances at the cutting and spread tables wereusually longer than the maximum of 32 inchesconsistent with good ergonomic design. Reach

distances should be reduced, but reaching is only apart of the entire task. Eliminating the more stressfulactivity to the back - lifting heavy rolls of material-may be enough to reduce workers’ back and shoulderpain.

The workstations at both plants were adjustable forheight and tilt, but for practical purposes, theworkstations were not conveniently adjustable.Many workers reported that it was too difficult andtime–consuming to adjust the workstations. Fromobservation, it was obvious that the adjustmentsneeded to be made during rotation would never beattempted. The issue of workstation adjustabilityand the range of heights needed to accommodate aheterogeneous workforce, provides some insight intothe difference between sitting and standingworkstations. The range in elbow rest height (abovethe seat height) for a sitting worker is about 4 inches(5th percentile female = 7.13 in., 95th percentile male= 11.6 in.) and about 10 inches when standing: (5th

percentile female = 36.9 in., 95th percentile male =46.8 in.), (Kroemer 1989). This means that aworkstation set at a fixed height, the reality at Auroraand Vanguard, would accommodate more workers ifthey could sit rather than stand.

In general, the manufacture of sewn garments andapparel goods requires a higher percentage ofproduction workers than other manufacturingindustries (80 % versus 70%) (Berg, et al. 1996).This explains why efforts to reduce the amount ofdirect labor in the industry have been the main meansfor manufacturers to cut costs and improveproductivity. TSS is a theory–based system whichaims to reduce the high cost of direct labor byplacing workers in modules, where entire assembliesare produced by a cross–trained team, rather thanhaving each worker produce the same subassemblyover and over. According to an organizationpromoting TSS (Americas 21st, Greenville, SouthCarolina), the module concept results in greaterproductivity per person through reduced handlingtime, having a fully–balanced line at all times,reduced effects of seasonal shifts and absenteeismdue to cross–trained workers, elimination of delayedhandling of repairs because flaws in product are


identified immediately, and overall reduction in staff.Irrespective of the extent to which modular systemsactually deliver on these promises (as recently as1992, only 9 % of the U.S. apparel industriespracticed the modular concept [Dunlop and Weil1996]), there is no mention that workers must standwith no possibility of sitting. The TSS conceptincludes rotation of workers through the variousstations in the module, but some of the tasks in themodules at both Vanguard and the Hill are longenough to make sitting, at least at one workstationper module, feasible without interrupting the flow ofwork. Indeed, many of the workers in the moduleswere not rotating anyway – they may as well havebeen sitting. This fact, coupled with the strong casefor sitting or sit/stand stations as the most appropriatefor the type of work performed in the modules (seeResults section), and the number of workersreporting foot and lower leg aches and pains fromstanding, points strongly for a sitting option in themodules.

Although workers reported aches and pains in theirlower extremity and feet, many liked performingtheir jobs while standing and said they would neverwant to go back to sitting all day. Standing andmoving around is good for the body. Compressiveforces at the low back are higher in the sittingpostures than when standing (Magora 1972).Moderate activity, such as rotating through tasks inthe cells, reduces foot swelling (Winkel andJorgensen 1986). However, there should be asensible balance between sitting and standing in anysedentary activity. For example, a recent study ofoffice workers whose workstations were modified toinclude sit/stand adjustable furniture found thatworkers felt more energetic and less tired by the endof the workday (Paul 1995).

The available literature shows that modular workcells do not necessarily allow operations to becompleted faster. They do show that allowing themodule to work as a smoothly running unit is moreproductive (Dunlop and Weil 1996; Berg, et al.1996). Video analyses of the time to complete worktasks in modules versus sitting at workstations(presented in Results section) are consistent with

what is stated in the literature in as much as theresults were inconclusive, indicating no significanttime difference between the two methods, and thatuse of the sewing machine is only 50% of the workcycle anyway. Actually, the principles of TSS werebeing circumvented by allowing workers not torotate, and by using the efficient module workers asmaterial handlers. These departures from theconcepts underlying the modules may have led toincreased reports of foot and leg pain (from staticstanding) and of shoulder and back aches and painsfrom having to lift rolls of materials and push carts offinished assemblies in addition to the other physicalactivities of their regular jobs.

CONCLUSIONS1. The workers at the Aurora Casket companyexperience many musculoskeletal aches and painsthat are related to the physical requirements of theirjobs, such as prolonged standing, lifting heavymaterials, handling finished materials, and reachingacross tables to cut materials. The long hours ofwork and other production pressures likely increasethe severity and/or duration of these health problems.

2. Standing while performing the various casketinterior–making tasks does not pose any additionalrisk to the workers versus sitting, except for theeffects on the lower limbs and feet due to prolongedstanding. 3. The unassisted lifting of rolls of material posesa high risk of back pain or injury to workers. This isparticularly the case with the cutters who liftmaterials and also reach across tables to cut materialand patterns. Of the two activities, the lifting posesthe greater risk of injury to the workers.

4. Panel assembly tasks are more suited tostanding than sewing tasks, but workers on both jobsneed the option of sitting during work and during restbreaks.


RECOMMENDATIONS

General1. Provide all workers, including cutters, panelworkers, and sewers, the option for sitting. This canbe accomplished by providing chairs or sit/standfurniture in the modules, or by dedicating one ormore workstations in the modules as sitting orsit/stand.

2. Provide more seating in the modules and breakareas so that everyone can choose to sit during restand lunch periods.

3. Provide material handlers for deliveringmaterials to the modules and to the cutting areas.The material handlers who deliver the rolls ofmaterial to the cutting areas should have appropriatematerial handling equipment. This could be a rollinghand truck with an adjustable height bed that can beraised or lowered to the height of the material on thestorage racks and similarly adjusted to the height ofthe machine or workstation to which it is delivered.Carts should have handle heights between 36 and 44inches, and the force to set the cart in motion shouldnot exceed 50 lbs.

4. Provide appropriate anti–fatigue mats forworkers to stand on while performing work tasks. Ifworkers stand without much movement, the matsshould be cushioned up to ½–inch thick to promotecomfort in the lower legs (Redfern andChaffin,1995). If workers are moving from station tostation in the cells, the mats should be cushioned, butthinner (up to 3/8 inch thick) to facilitate walking andprevent tripping. Mat edges should be beveled formaximum safety and ease of sweeping..

5. Evaluate and address the environmental andsocial causes of stress that affect the workers’ health,job satisfaction, and productivity.

Cutting1. Provide a shorter handle or a T–shaped grip onthe handle of the wadding machine to avoidexcessive shoulder flexion and extension whilemoving the shear along the cutting track. Also, adda stop on the track to control how far the shear movesto cut materials less wide than the track.

2. Reduce the width of the cutting tables so thatreaches do not exceed 32 inches. If this modificationto the spread table is not feasible, determine if backand shoulder aches and pains can be remedied byeliminating the need to lift and handle rolls ofmaterial.

3. Relocate the bar code machine on the cuttingtable at Aurora to eliminate the need to bend over toaccess the keypad. The keypad should be located attable height and tilted away from the worker for easyvisibility (ensuring also there is no glare). The top ofthe keypad should not exceed 42 inches.

Cells1. Redesign all workstations for easyheight–adjustment by workers. Table tops equippedwith a counterbalanced height adjustmentmechanism will allow workers to adjust the heightwith one squeeze of a bar that locks into positionwhen she takes her hand off the bar. As a minimum,the tables should be adjustable between the ranges of36.5 – 40.5 inches.

2. Modify the workstations in the Vanguardsewing cells to be more stable, and include troughs infront and back to prevent long pieces of materialfrom making contact with the floor.

3. Relocate materials storage shelves on the panelworkstations so that all materials are above theheight of the work surface to allow for easy accessand elimination of the need for workers to moveaway from the workstation while retrieving somepanel components.


4. Counter–balance staple guns in the panelmodules so that the workers do not have to bear theweight of the tool when using it.

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Armstrong TJ; Buckle P; Fine LJ; et al. [1993]. Aconceptual model for work–related neck andupper–limb musculoskeletal disorders. Scand JWork Environ Health 19:73–84.

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factors at work in relation to back and limb disorders.Scand J Work Environ Health 21:134–42.

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Table 2Frequency Multiplier (FM) for NIOSH Lifting Equation

FrequencyLifts/min

Work Duration

< 1 Hour < 2 Hours < 8 Hours

V < 75 V > 75 V < 75 V > 75 V < 75 V > 75

0.2 1.00 1.00 .95 .95 .85 .85

0.5 .97 .97 .92 .92 .81 .81

1 .94 .94 .88 .88 .75 .75

2 .91 .91 .84 .84 .65 .65

3 .88 .88 .79 .79 .55 .55

4 .84 .84 .72 .72 .45 .45

5 .80 .80 .60 .60 .35 .35

6 .75 .75 .50 .50 .27 .27

7 .70 .70 .42 .42 .22 .22

8 .60 .60 .35 .35 .18 .18

9 .52 .52 .30 .30 .00 .15

10 .45 .45 .26 .26 .00 .13

11 .41 .41 .00 .23 .00 .00

12 .37 .37 .00 .21 .00 .00

13 .00 .34 .00 .00 .00 .00

14 .00 .31 .00 .00 .00 .00

15 .00 .28 .00 .00 .00 .00

>15 .00 .00 .00 .00 .00 .00

† Values of V are in cm; 75 cm = 30 in.


Table 3Coupling Multiplier (CM) for NIOSH Lifting Equation

Couplings V< 75 cm (30 in) V > 75 cm (30 in)

Coupling Multipliers

Good 1.00 1.00

Fair 0.95 1.00

Poor 0.90 0.90


APPENDIX A

The Factors Comprising the NIOSH Revised Lifting Equation

Calculation for Recommended Weight Limit

RWL = LC * HM * VM * DM * AM * FM * CM(* indicates multiplication.)

Recommended Weight Limit

Component Metric U.S. Customary

LC = Load Constant 23 kg 51 lbs

HM = Horizontal Multiplier (25/H) (10/H)

VM = Vertical Multiplier (1–(.003*V–75*)) (1–(.0075*V–30*))

DM = Distance Multiplier (.82+(4.5/D)) (.82+(1.8/D))

AM = Asymmetric Multiplier (1–(.0032A)) (1–(.0032A))

FM = Frequency Multiplier (From Table 2)

CM = Coupling Multiplier (From Table 3)

Where:

H = Horizontal location of hands from midpoint between the ankles. Measure at the origin and the destination of the lift (cm or in).

V = Vertical location of the hands from the floor.Measure at the origin and destination of the lift (cm or in).

D = Vertical travel distance between the origin and the destination of the lift (cm or in).

A = Angle of asymmetry – angular displacement of the load from the sagittal plane.Measure at the origin and destination of the lift (degrees).

F = Average frequency rate of lifting measured in lifts/min.Duration is defined to be: < 1 hour; < 2 hours; or < 8 hours assuming appropriate recoveryallowances.


APPENDIX B

Worker Comments and Body Maps

Comments from Aurora workers

Hill – panels

S when put table up (i.e. raised height) once, was told was too high and unsafe for othersS people hurt cranking tables – not easy to doS exit blocked by cutting table and can’t open in summerS need a chair – have to sit on floor at break – break area isn’t big enough (for all)S extra break when overtime is involvedS stress is far greater on us than the workS need a chairS need extra break when we work 9–10–11 hoursS has had cortisone shots in elbow four timesS need a chair for breaks and lunch – “We stand all day and a chair isn’t too much to ask for.”S break area isn’t large enough for everyoneS extra break for time over 8 hoursS “The stress factor is 10 times worse than the physical labor.”S need a chair to sit on for breaks and lunch. “After standing you need to sit.”S lunch area’s not big enough for everyoneS “Adjusting tables after a tall person is on it is hard on your back. They make everything for tall people

(hard to get your supplies for shorter people).”S they took all the chairs outS “The cells are to (sic) stressful and to (sic) close with people and different personality’s (sic). I will

stress the cells are very stressful and tension is awful.”S staples too small so catch fingers on them and bleed

Hill – sewing (cells)

S “I put Pillow Fill down because that (sic) my regular job.”S “I’ve been on different jobs for over yr. I was in Panel Cluster Jan. 97 to Feb. 98. The pain was better

while working in cluster till they started up the night cluster. The shelves was to high for me to reachbecause of being short plus I already had problems with my shoulder and back, really my whole rightside.”

S “I went to chiropractor on my own because of problems I ‘d had before.”S “My problems was caused from the way we use to do my job and machine, since they have put new

pillow machine in it’s lot better.”SSSS “I’m glad we get to change around where we didn’t before.”S “Why is there no lights that come on when electric goes out or exit signs?”S “After standing over long periods of time, I begin to ache in legs and feet and sometimes in left hip

area.”


S “Machines are hard to roll up to position we need them.”S “Sometimes material is hard to unload especially if a lot of velvet.”S “Since I’ve been standing I’ve noticed more broken veins in my legs that I did not have before.”S “I like the process, verses (sic) sitting all day. I enjoy doing the different kinds of work. I don’t fall

asleep on the job now. I love the machines, being able to adjust.” (Worker with more than 20 yearswith company)

S “I think the most problem will be for the ladies that has sat for 10 to 20 years.” (Worker under 30 yearsold, in plant 3 years)

S “I’ve always sat and sewed and loved it and reached up to hand the finish interiors onto a overheadconveyor why my right shoulder problem started. I can live with it but there is a ouch in there a certainmovement. Then in January 98 we were forced into standing in clusters/cells to sew like ostriches.Most weight on left foot while we work pedals with right foot and started OK but soon my arch andheels stated hurting and now it’s gone up into my left ankle. The longer the day the worst it hurtsstanding on it. Standing is definitely taking a tool on this body. I get sharp pains sometimes in my hipand back and wonder what my life will be in 10 – 12 years yet to go to retirement? I feel standing andsitting part time would be better than standing all the time.”

S “I love sewing but not stress is because of pressure to get quotas. Rush, Rush Rush to get it out andno room for mistakes and I hate sloppy work and with all the flaws it’s ridiculous. Cells is not theanswer to good quality work when rush any old way to get it out. (Say the person next to you doessloppy work and you have to straightening out their mess.) Blood pressure medicine and cortisoneshots for joints and diet, diet, diet.”

S “Fumes and ventilation is also sometimes a problem in our department. No fresh air unless you overby the door. Headaches – eyes burn – not looking forward to summer 90º weather – humidity andmaterial stick. Rush. Need air conditioner.”

S “I wonder if standing on concrete will cause vein problems, knee or hip joint problems.”S “Sewing buggy pillow’s (sic) especially premium velvet ones and having to turn inside out. Very hard

on your arm’s. Having to stand for more than 8 hrs. A day. Should be able to sit down for at least partof day if you so choose.”

S “I have had a stand up job at one time. The next was all sit down job. Now I have a job where I sit awhile then stand a while. This job I have now seems to be a lot easier on my body. We need chairsto sit down on at breaks and lunch. Especially all stand up areas.”

S “I had carpel tunnel (sic) surgery resulting from my job. Now I have tendinitis (sic) in my left elbowand was sent to co. Doctor for it but it still hurts. I also have fibrositis which seems worse with overlypushing or shoving. It is extremely (sic) hot during the summer and now we aren’t even allowed tohave the doors open.”

Hill – sewing (old)

S “If I am on my feet and legs very much I have a lot of great pain. (I am on a sit down job.)”S “It is extremely hot in here in the summer ( no air circulating).”S “Everything is so congested (sic) that I think it is ver unsafe.”S “The trucks with the cluster work are very unsafe, 1) the way the pipes stick out and right at eye level.

2) they are too hard to push around.”S “Always feel so pressured that my blood pressure is high. Very stressful!”S “Get headaches because of fumes.”S “If ever a fire it will be hard to get out because of everything in the way and so far to go to get out.”


S “They expect us to do a certain amount of work a day but keep giving you more to do.”S “In the summer it is very hot in this department. There is one large door they use(sic) to open in the

past. They are not opening it this year because they put the material spreader in front of it. We haveno windows to open or no fresh air vents toward the back of the room. A lot of people get sick becauseof the heat in the summer. We also have a lot of heat coming from the office air conditioner.”

S concerned about having to move cranks in new cellsS buggies worst – turning hurts shoulder – so does blanket – “You use all your strength to pull.”S CTS surgery 3 years ago on left wrist – sometime swear braces on both wrists – still have lots of

problemsS told if not here when start training, will be put anywhere, so waiting to report problemsS concerned about new machines not being high enough because of her height and the need to control

the fabric when sewing (she does it with arm and elbow)S “I can see hip and leg injury in the future with the stand up jobs because they stand with all the weight

on one leg.”S “Injury to back, shoulder, and neck when moving tables in sew cell up and down.”S “Stool might help cut down on hip and leg injury. It could help give them a little more support.”S “Area surrounding it is so congested that they would be unable to get out ver fast which could cause

a fall with injury. Bad posture can cause harm in neck, shoulder and back for both standing and setting(sic).”

Hill – cutting

S treated for stress, which doctor links to workS trucks used to deliver work to cells are difficult to manoeuver – design’s only been in use for about 6

monthsS carpal tunnel surgery on both wrists in Dec./97 and Jan./98S “I’m being treated for high B/P caused by hypertension and have headaches. Very much stressed out,

I feel that it is caused by the job change.”S “The summer heat is going to be bad because we can’t open the door and we can’t turn the fans on

because it blows the material. All the air we get is 2 little windows with slats.”S “Stress is the main factor right now. I feel I am giving 100% but at the present that doesn’t seem to be

enough. It is better on nights than days.”S too hot, can’t open door because of new cutting machineS can not use fansS there are extra heavy rolls so much extra liftingS “TOO MUCH STRESS.”S “everyone is lifting, pushing, pulling, standing in one place causes as much pain as moving about”S could lift 38–pound rolls 50 – 100 times a day, depending on what doing (could be hand cutting, using

spreader)S “Summer heat. We only have 2 small windows with slats, no air conditioning for us but we get heat

and fumes off office air conditioners. We have fans but can’t use them because of new cutting system.We have a big garage door but can’t open it because of new cutting system. We have no way to getany fresh air.”

S “We are also extremely tired because of overtime.”S “The stress we are all under has caused my menstrual cycle to become irregular and other women are

also having the same problem. My doctor told me it was due to stress I was under.”


S “The new furnace put out gas from a leak and made us all sick. They said it is fixed but it still acts up.”S “Trucks for work are very hard to move and some have wheels that don’t move at all causing excessive

straining.”S “We were denied new mats.”S “The circular saw doesn’t stop very quick after it is turned off and is very heavy.”S “Have complained about bolts of material being too heavy but nothing is done. They could put less

yardage on bolts.”S “Too many cords hanging in the way down on lay cutting area. One girl accidently cut through a cord

and sparks started flying.”S “The pressure and tension in here is at its worst.”S “We are all scared of the spreader when the material gets stuck in the belt. We are afraid of getting our

hands caught in belts.”S very hot in summer – with closing door, “will be no air flow this summer”S too much forced overtimeS “Stress, it’s an all over my body experience. Overtime is a killer. Too much forced overtime. S The stress has messed up my periods, female area. S “Moving the trucks around that are so hard to move hurts the arms and legs. Also I tripped (sic) over

the legs of the trucks. Very dangerous.”S Summer time. When it’s hot in here the office has there (sic) air conditioner on and the hot air from

the air conditioner is on us. This summer will be worse. We are not allowed to open big door for freshair that we are accustomed to.

S “We had a gas leak in here one time. That was fun. Nobody did anything about for about 2 hours.”S “Accidents are not treated quickly enough. An accident should be taken care of immediately!”S “When I fell at 6:00 AM I was not allowed to leave to go to the Dr. or E.R. until 8:30. And then only

at my instance (sic). I worked for 2 hours before I went to the E.R.”S still have pain but not all the time, from lifting

Vanguard – panels

S “Health–wise – break rooms and bathrooms nee attention every day, not just once a week. If peopleare temporary (sic) in a dept. I feel they should be taught everything there is to do and not just borethem with one thing to do all the time. It also makes it easier on the senior people to be able to switchto other jobs that will make it a little less monotonous (sic) on us.” (19 years seniority)

S bid job is roll/panel but fill in for absent sewing and cutting workers S “Jack of all trades” is job do most often, working for company 10 + 18 yearsS break area not clean – stuff spilled on floor – trash cans should be dumped dailyS women’s bathroom needs better cleaningS janitor’s job eliminated – needs to be replaced so can keep areas clean

Vanguard – sewing (cells)

S complained to employer and workers’ comp but won’t help herS had two CTS surgeries (July/97 and August/97) – doc told her not to return to job but company

switched doctorS feel intimidated by management to keep mouth shut


S could hardly walk when cells introducedS super said was “in your head” ––> so “mad and upset” put up with for a day and then insisted on seeing

a doc who sent her to chiropractor–rheumatologist, not covered by compensationS lots of stress, more than there ever used to be – team now, problem if one insists on doing things their

way or other person doesn’t do the jobS “When we work 10 hours standing make back and legs hurt worse.”SSSS “I think for myself the machines should be at a height (sic) to suit the person working on it. The

machine’s (sic) should be made to let up and down quickly to save time.”

For Information on OtherOccupational Safety and Health Concerns

Call NIOSH at:1–800–35–NIOSH (356–4676)

or visit the NIOSH Homepage at:http://www.cdc.gov/niosh/homepage.html

!!!!Delivering on the Nation’s promise:

Safety and health at work for all peoplethrough research and prevention

Documents

HETA 98–0085–2715 Aurora Casket Company Aurora, … · Aurora Casket Company Aurora, Indiana Daniel J. Habes, M.S.E., C.P.E. ... The finished caskets are made of metal, having